Portable ambulant pneumatic compression system

ABSTRACT

An automatic portable ambulant miniaturized system for applying pneumatic pressure to a body limb including a portable ambulant hand-held fluid source unit, a conduit for delivering fluid generated by the unit, and a sleeve coupled to the conduit and adapted to envelop a body limb. The sleeve contains one or more individually inflatable cells, each cell being subdivided into two or more longitudinally extending confluent compartments along the axis of the body limb. The compartments are inflated and deflated essentially simultaneously by the portable fluid source unit.

PRIORITY INFORMATION

This application is a continuation-in-part of co-pending U.S. patentapplication Ser. No. 09/038,157 filed Mar. 11, 1998, and is related toco-pending U.S. patent application Ser. No. 09/375,083 filed Aug. 16,1999.

BACKGROUND OF THE INVENTION

The invention relates to systems for applying compressive pressuresagainst a patient's limb, specifically to a miniaturized, automaticportable ambulant system.

Various conventional compression devices are known for applyingcompressive pressure to a patient's limb. These types of devices areused to assist in a large number of medical indications, mainly theprevention of deep vein thrombosis (DVT), vascular disorders, reductionof edemas and the healing of wounds. Prior art devices are typicallydivided into two main segments: 1) a hospital segment, in which they areused mainly for the prevention of DVT in patients with high risk fordeveloping the same, and 2) a home segment, in which they are mainlyused to treat severe lymphedema.

Although showing high clinical efficacy in treating the above clinicalindication, prior art devices share the following disadvantages. First,they use the conventional main power supply (wall outlet), and thusimpose total confinement on the patient during treatment. The pump unitis heavy (5-15 pounds), which makes it hard to maneuver and place in thevicinity of the patients. The pump unit is big and thus creates astorage problem, specifically in hospitals, in which a few units arestationed, usually in a special storage room. The sleeve is big andungainly, and thus restricts the movement of the limb it encompasses andimposes an aesthetic discomfort. In addition, the use of multiple cellsdemands the use of multiple conduits (usually one for each cell) makingthe whole system more cumbersome and harder to maneuver. All of theaforementioned disadvantages result in poor patient and therapist(mainly nurses) compliant, resulting in that the devices are used fortreatment only to the most severe cases of the medical indicationsdescribed above.

Prior art devices need to be as big and use the conventional electricaloutlets for the power supply as they all use the same basic shape ofinflatable bladders for their sleeves. These devices use substantialamounts of fluid (usually air) in order to inflate the sleeve and createthe desired pressure at a timely manner (between 0.25-10 seconds perchambre). As a consequence, the devices need a large compressor thatrequire high current supply, which forces their connection to theelectrical outlets for power supply. The same follows with respect tothe need for relatively large components in the prior art devices, suchas solenoids, air conduits etc.

The need for a small ambulant/portable aesthetic device has long beenrecognized by the industry, as evident from prior patents of leadingcompanies in this field. Patents such as U.S. Pat. Nos. 5,795,312,5,626,556, 4,945,905, and 5,354,260, as well as EP 0861652, and others,are concerned with using less air to inflate the sleeves, easierhandling, especially with the connection of the pump unit to the patientbed, and all of the other disadvantages previously discussed.

A step in this direction was the introduction of foot pumps. Still, asscientists and engineers were fixed on improving the pumps (their flowrate, power consumption etc.) and not on improving the use of the pumpedair (as described in the related U.S. patent applications of theapplicant, that enables one to accomplish the same pressures in the sametimely manner and the same therapeutic goals with about {fraction(1/10)} of the volume of air prior art devices need), no majorbreakthrough in the size of the sleeve/ pump unit, its power source ormobility during use were accomplished until the present invention. Asmall, ambulant, portable device will achieve the following needs thatprior art devices could not accomplish. First, patients will gain thefreedom of movement without treatment interruption. Currently, patientsin hospitals which are connected to prior art devices for 5 consecutivedays following their operation cannot move from their beds unlesstreatment is interrupted, e.g., each time the patient needs to use thebathroom or move around, the nurse has to come unhook the patient fromthe device and afterwards reconnect the patient to the device. Homeusers of prior art devices (mainly patients suffering from acutelymphedema) have to confine themselves to one place during treatment andare restricted from basic mobility needs such as the use of bathroom,opening the door, etc. Second, it will be easy to use and handle.Currently, patients being discharged from the hospital are stopped fromtreatment by the device, although still considered under high risk fordeveloping DVT, as the earlier described disadvantages (size, weight,mobility) of the devices makes them almost unsuitable for self use athome, especially when dealing with the elderly population. Nurses in thehospital are bothered by the need to connect and disconnect the manyconduits most of the devices use and to carry and place the devices,from the storage room to the patient bed, back and forth. These are timeconsuming actions that need to be done whenever a new patient arrives,or if a fault arises in the device during operation or if the patient ismoved for a short time from his or her bed. Third, it will eliminate thestorage problem, with conventional devices there is a need for a storageroom, mainly in the hospitals in which there are a few pump units andsleeves. Fourth, it will enable the user (mainly the home user) to getengaged in social activity during treatment. Conventional devices imposegreat aesthetic discomfort and thus restrict the home user from anysocial activity.

By achieving all the above needs, the new compression system will besuitable for use not only for severe cases of medical indicationrelating to the healing of wounds, reduction of edemas, vasculardisorders and the prevention of DVT, but also to the mild cases, forwhom, until now, the only alternate solution was the use of elasticstocking which are, clinically, inferior form of therapy compared withpneumatic compression systems.

SUMMARY OF THE INVENTION

In accordance with one embodiment of the invention, there is provided animproved system for applying pressure against a patient's limb. Thesystem introduces a miniature, battery operated (rechargeable), ambulantpump unit, the size and weight of a personal radio, connected to aninflatable sleeve for use on a limb. The system can operateindependently of a fixed power source as it uses small rechargeablebatteries. The system can also operate while connected to a conventionalelectrical outlet, at the time of such operation or at any other time itis connected to the electrical outlet, the system will automaticallyrecharge itself.

The system provides a pump unit that can be carried around whileoperating, connected to an aesthetic flexible inflatable sleeve that caneasily be concealed, for example, under trusses. The sleeve has aplurality of cells arranged longitudinally along the sleeve from thedistal part of the limb to which it is applied, to its proximal part.Each cell is subdivided into two or more longitudinally extendingconfluent compartments that are inflated and deflated essentiallysimultaneously. The system has means for intermittently inflating thecells during periodic compression cycles, and means for intermittentlyconnecting the cells to an exhaust port.

In one aspect of the invention, the pump unit can be operatedalternatively as a foot pump, calf pump or a simultaneous foot and calfpump. In another aspect, a combination of self operated relief valvesand check valves can be used for the inflation and deflation of thesleeve cells, thus achieving additional compactness and lower powerconsumption of the pump unit, and uses only one air conduit between thepump unit and the sleeve. In yet another aspect, while the system isconnected to a conventional electrical power outlet, the rechargeablebatteries can be bypassed and recharged only if necessary, thusexpanding their life expectancy. Yet in another aspect, the pump unitcan use an accumulator in order to speed the time needed for theinflation of each cell.

Accordingly, the invention provides a system for applying compressivepressure to a limb in which the pump unit is small, light weight,ambulant and can operate independent of electrical power supply outlets,and utilizes a small flexible inflatable sleeve placed on a treatedlimb, thus enabling the freedom of movement of the treated person. Theportability of the system allows for easy handling, placement in thevicinity of the patient, storage, and does not disturb the patient orsurroundings during treatment.

In a further aspect of the invention, only one conduit is used from thepump unit to the inflatable sleeve, regardless of the amount of cells inthe sleeve, thus greatly simplifying connection to the sleeve andimproving patient compliance as numerous conduits usually restrictmovement. The configuration enables reduction in the size of the pumpunit, reduces current consumption of the pump unit and allows for longerindependent operation. In addition, the system can utilize a connectorbetween the pump unit and the conduits to the sleeve that is able todecide the needed treatment, thus eliminating the risk of choosing thewrong treatment, especially when more than one limb is treated and thetreatment is asymmetric.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration showing a massage sleeve according to theinvention in use on the leg of a patient;

FIG. 2 is an illustration of a massage sleeve according to the inventionmounted on the leg of a patient drawn to a larger scale;

FIG. 3 is a partial perspective view of a massage sleeve according tothe invention fitted with a control unit;

FIGS. 4A and 4B are cross-section views of a cell in the deflated andinflated states, respectively;

FIG. 5 is a block diagram of a pneumatic pressure system according tothe invention;

FIG. 6 is a schematic block diagram of a pump unit that corresponds tofurther details of the pump unit of FIG. 5;

FIG. 7 is a table of programmed control parameters for a control unit inthe case of two three-chambered sleeves according to the invention;

FIGS. 8A-8E illustrate a flowchart of an exemplary operation of thesystem in accordance with the invention;

FIG. 9 is a block diagram of an alternative embodiment of a pneumaticpressure system according to the invention;

FIG. 10 is a schematic block diagram of a pump unit that corresponds tofurther details of the pump unit of FIG. 9; and

FIG. 11 is a simplified functional block diagram of an exemplaryconnector assembly in accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following, an embodiment of the invention will be described foruse on the leg of an individual. However, it is to be understood thatthe invention is also intended for use on any body limb such as an arm,a foot, a part of a leg, arm or foot, and may be used on two or morelimbs simultaneously.

In FIG. 1, a patient is depicted wearing a massaging sleeve 1 of theinvention on her leg while carrying out her routine duties. In FIG. 1,the trouser leg of the patient is cut away to reveal the sleeve. Inpractice, however, the sleeve remains concealed from view, and remainsunnoticed even during operation when the cells are intermittentlyinflated. The sleeve 1 has an inner and outer surface composed of adurable flexible material and is divided into a plurality of cells 2along its length and each cell is connected to the control unit 3 by aseparate tube collectively labeled 4 in FIG. 1. Sections of the sleevemay be of non-inflatable elastic material 5, for example around the kneeand ankle.

As can be seen in FIGS. 2 and 3, each cell has a fluid inlet opening 6to which a hose 4 from the control unit 3 is attached. The control unit3 contains a compressor capable of compressing and pumping ambient airinto one or more selected cells in the sleeve via the hoses 4. Thecontrol unit 3 allows a temporo-spatial regime of inflation anddeflation of the cells to be selected, e.g. a regime which generatesperistaltic contractions of the sleeve so as to force fluids inside thelimb towards the proximal end of the limb, or a regime which enhancesthe flow of the venous blood in the limb. The continuity of theperistaltic wave is enhanced by interdigitating the compartments ofadjacent cells in the massaging sleeve as shown in FIGS. 2 and 3.

In accordance with the present invention, the cells are subdivided intoa plurality of longitudinally extending compartments 7. The compartmentsare formed, for example, by welding the inner and outer shells of themassaging sleeve along the boundaries of the compartments. Thecompartments in a given cell are confluent due to perforations 8 in theseams between adjacent compartments so that all the compartments in thecell are inflated or deflated essentially simultaneously. Eachcompartment, when inflated, assumes essentially the shape of a cylinderhaving its axis parallel to that of the limb.

A cross-section of a deflated cell is shown in FIG. 4a, and FIG. 4bshows the same cross-section after inflation. The cell has been divided,by way of example, into ten identical compartments, it beingself-evident that any other number of compartments may be used. If N isthe number of compartments in a given cell, and r is the radius of aninflated compartment, then as can be seen in FIG. 4b the length of thecircumference 10 that passes through the centers of the inflatedcompartments will be 2Nr, whereas the circumference 9′ of the deflatedcell is Nπr. The fractional decrease in the circumference upon inflationis thus $\begin{matrix}{\frac{{N\quad \pi \quad r} - {2{Nr}}}{\pi \quad {Nr}} = {{1 - \frac{2}{\pi}} = 0.36}} & (1)\end{matrix}$

The length of the inner circumference 9″ of the inflated cell will beless than 2Nr so that the fractional decrease in the inner circumferenceupon inflation is thus greater than 0.36.

N and r are chosen so that πNr (the circumference of the deflated cell)corresponds to the original circumference of the limb segment containedwithin the lumen of the cell. The fractional decrease in thecircumference of the cell upon inflation (0.36) causes a contraction ofthe cell whereby pressure is applied to the limb that, as follows fromequation (1) above, is independent of N and r. Thus, by choosing Nsufficiently large, and r correspondingly small, a sleeve is obtainedhaving an inflated outer circumference not substantially larger than theoriginal circumference of the limb. This is in contrast to prior artdevices, which must have a circumference 36% greater than the initialcircumference of the limb in order to achieve the same applied pressureas that produced by the present invention.

Letting now L be the length of a cell and C=Nπr, the initialcircumference of the limb contained within the cell, it is readilyappreciated from FIG. 4 that the initial volume of the limb containedwithin the deflated cell is$V_{D} = {{{\pi ( \frac{C}{2\pi} )}}^{2}{L.}}$

The final volume of the limb contained within the inflated cell is lessthan$V_{1} = {{{{\pi ( \frac{0.64C}{2\pi} )}}^{2}L} = {0.41{V_{D}.}}}$

Inflating the cell thus leads to a decrease in the volume of the limbcontained within the cell of about 59%. This represents the volume offluid squeezed out of the limb, or the work performed by the sleeve.This is accomplished by inflating the compartments of the cell to atotal volume of V_(T)=Nπr²L=${N\quad \pi \quad ( \frac{C}{N\quad \pi} )^{2}L} = {\frac{C^{2}L}{N\quad \pi}.}$

In contrast to this, obtaining the same decrease in the volume of thelimb by prior art methods requires inflating a cell to a final volume of$V_{F} = {{\pi \{ {( \frac{1.36C}{2\pi} )^{2} - ( \frac{0.64C}{2\pi} )^{2}} \} L} = {\frac{C^{2}L}{2.8\pi}.}}$

Thus, when the number of compartments in the cell of the presentinvention is at least 3, the volume to which the cell must be inflatedis less than that of prior art devices. Moreover, by choosing Nsufficiently large, a decrease of 59% in the volume of the limb can beobtained by inflating the cell to an arbitrarily small total volume. Forexample, when N=30, the total volume of the inflated cell is less thanone-tenth of the volume of the inflated cell of the prior art devices.This allows a much smaller compressor to be used than is possible withprior art sleeves, thus permitting the patient to be ambulatory whilebeing treated by the invention.

It is noted that a sleeve according to the invention, e.g. such assleeve 1 in FIGS. 1 and 2 or a smaller sleeve covering only a portion ofa limb, may be used for immobilization of a fractured bone in a limb.

FIG. 5 is a block diagram of a pressure system 50 includes a pump unit51, which utilizes an electrical power supply/charger unit 55, such as aconventional electrical wall outlet, and an inflatable sleeve 52. Thesleeve has a plurality of cells 53 arranged longitudinally along thesleeve. The pump unit and the sleeve are connected by conduits 54. Thesleeve is placed over a limb and inflated, from its distal part to itsproximal part in some desirable cyclic manner by the pump unit, thuscreating the desirable pressure cycle on the limb. It will beappreciated that the system can include at least one or more flexiblesleeves 52 with single or multiple inflatable cells 53 adapted to be incontact with the body part to be treated. The best selection of a sleeveis one that requires small volume change to exert the needed pressure.

FIG. 6 is a schematic block diagram of a pump unit 60 that correspondsto further details of the pump unit 51 of FIG. 5. It will be appreciatedthat the thick interconnecting lines represent pneumatic connections,while the thin interconnecting lines represent electrical connections.The pump unit 60 includes an independent source of energy, such as arechargeable battery pack 67, which enable the pneumatic deviceoperation without a fixed connection to a main power outlet. Thebatteries can be bypassed and the device is able to operate for longertimes, and the batteries can be recharged at the same time, while it isconnected to the main power supply with the aid of the charger 55 (seeFIG. 5).

A source of compressed air, such as a compressor 64, is powered by thebatteries or the main electrical outlet, and connected to the sleeve orsleeves 52 by pneumatic conduits 54. A control unit 68 is adapted toreceive inputs from the operator and from pressure sensors 62,63. Thecontrol unit serves to read and control the operation of the compressor64 and to control the cyclic inflating and deflating of the sleeve 53.The control unit also controls the operation of solenoid valves 66 andpressure relief valve 61, which receive and distribute the flow to thedifferent cells 53 with the aid of a manifold 65, to enable thesequential inflating and deflating of the multi-segmented sleeve's cells53.

The use of miniaturized components like the compressor 64 and solenoidvalves 66, together with the miniature accessories, results in smallpower consumption that enables the operation of the pneumatic device onbatteries, while maintaining small dimensions and light weight of theoperating unit. The use of a sleeve 53 with a small-inflated volume willimprove the obtained results of the operation unit for better clinicaloperation and results.

The operation of the system of the invention will now be described.Pneumatic devices apply cyclic sequential pressure on a body's legs orarms. The cyclic sequential pressure is applied on the treated parts ofthe body by inflating and deflating each cell 53 of the sleeve 52 at apredefined timing. While being inflated, the multi-chambered segmentedsleeve 52 should be encircling the part of leg to be treated. While thesleeve is inflated, a local pressure is applied at the contact areabetween the sleeve and the body.

The control unit 68, which can be software based, controls the operationof the compressor 64 and solenoid valves 66. The control unit can beprogrammed to achieve any desired inflating and deflating sequence andtiming including delay intervals, in accordance with clinicalapplication. For example, in the case of two three-chambered sleeves(six solenoid valves), the controller can be programmed to operate inaccordance with the table of parameters for the control unit shown inFIG. 7.

Each time interval from the table (T1, T2, . . . , T7) can be changedindependently. The pressure level of the treatment can be controlled bythe patient or the therapist. An example of an exemplary operation ofthe system in accordance with the invention is illustrated in theflowchart of FIGS. 8A-8E, describing self-checks and error detectionprocesses, as well as normal operation of the system.

In FIG. 8A, the operation begins with on power reset (cold or hot) 801.The system initializes a built in test (BIT) procedure which checks thedisplay, the buzzer and the pressure sensors (802,803,804). If thesensors are found to be activated at this stage, the system holds(through termination procedure ((806) and 837-840)). If the BIT endscorrectly, the system resets the watch dog timer (WDT) which preventslocking of the system and turns on the ON Flag (on the display) (805),and enters the WAIT mode, where it waits for a program (treatment)selection.

A WAIT procedure starts at step (805 A) where keys are checked. If keysare not pressed, the system blinks the program flags at the display(807). If more than 1 minute has passed without any key pressed (808),the system enters error mode 1 ((809) and (841-845)). Restarting thesystem is the only way to go back from this mode of operation.

If a program key is pressed, the system de-bounces for 0.5 sec and thenchecks the keys again (810). If no key is pressed after the de-bouncetime, the system returns to the start of the WAIT procedure. If a key ispressed after the de-bounce time, the system turns on the selectedprogram flag (on the display) (812), and after a 0.25 sec delay (813)resets the WDT and starts the sequencer procedure (815).

With reference now to FIG. 8B, at the first stage in the procedure readsthe program group (Dip Switch) on the board (816). Note that this switchis hidden from the user. At that time, the requested treatment programis well defined, and the system starts loading data (817). This data canbe loaded from two different sources, one a preloaded sequence which ispart of the content of the system controlling processor. The secondsource is the sleeve itself, equipped with a special connector andinternal memory, which enables special treatments to be supported (plugand play procedure) (Detailed data of this procedure provided in(864-868). After the sequence has been loaded, the WDT resets again, anddata is entered to the cycle counter (which holds the sequence data, aspreviously supplied) (818).

The sequence starts by moving data to the pump and the valves andcontinues with a short period delay before checking the pressure sensors(820). Until this delay is finished, the system waits (820-821). Afterthat, the system checks the sensors (823). If the sensors do not reactcorrectly until the max available time (823, 824, 822), a sequence steperror is stored (825). Later on, those errors will be analyzed(830-836). If the sensors reacted correctly at the time window, anon-error flag is stored (826). The system branches to the erroranalyzing procedure (827 and 830). If the system returns (not enougherrors to hold), the cycle step counter advances (828, 829) and the nextstep starts (819).

In FIG. 8C, the error analyzing procedure (830) starts by storing thelast calculated error flag in a 24 bits long FIFO register (831). Thenumber of errors in the register is counted (832) and if the numberexceeds 2, i.e., 3 errors in 24 steps, the system starts a HOLDprocedure (835,836). The HOLD procedure starts turning off the ON flagon the display, and turning on the ERROR flag, and then proceeds to thetermination procedure (837-840).

If the number of errors does not exceed 2, the system initializes theWDT and returns to step (827) and continues. The termination procedureis as follows. The termination procedure starts at step (837) byoperating the buzzer (838), and waits 10 seconds (839, 840) beforere-operating the buzzer.

In FIG. 8D, an error 1 procedure is described. The error 1 mode startsat step (841), operates the buzzer 3 times, waits 1 minute (843), and iftime from start (841) did not exceed 10 minutes (844), it repeats thebuzz procedure. If yes, the system moves into the termination procedure(845 and 837).

The WDT procedure starts at step (846), by resetting and re-programmingthe WDT counter to a 1 second interval. If, within this time interval(847) no WDT initialization pulse arrives (848), the WDT will reset thewhole system (850).

A battery check procedure (855-859) are hardware mechanisms that operateindependently, without the software. An external supply check procedure(860 to 863) are hardware mechanisms that operate independently, withoutthe software.

With reference to FIG. 8E, an internal/external sequence loadingprocedure is shown. This unique function of the system enables use ofboth pre-loaded treatment sequences in the pump unit processor(internal) and to receive new treatments parameters from an electronicunit placed within the sleeve's connector (external). The sleeveconnector to the system includes, together with the air tubes, anelectronic memory and/or processing device, the presence of which isdetected by the system. Detecting such a device causes the system toload the sequence data from the sleeve memory, and not from thepre-loaded memory which is part of the processor. This is referred toconventionally as a “plug and play” mechanism. The procedure starts atstep (864), then the system checks the presence of an intelligent sleeve(865). If one exists, the sequence is loaded from the intelligent sleeve(867). If no intelligent sleeve is detected, then the pre-loadedsequence is loaded (866). Finishing loading the system causes theprogram to return to the next step 817.

Additional miniaturization and mechanical simplification of the portableambulant pneumatic pressure system of the invention can be achieved byintroducing self-operated relief valves replacing the controlledoperated solenoid valves. Another embodiment of a portable pneumaticpressure system 90 of the invention is illustrated in FIG. 9. The systemincludes a pump unit 91, at least one inflatable sleeve 92 with a singleor multiple inflatable cells 93 adapted to be in contact with the bodypart to be treated.

An independent source of energy, for example rechargeable batteries, isprovided which enables the pneumatic operation without a fixedconnection to a main electrical power outlet. The batteries can bebypassed and thus system can operate for longer time periods while it isconnected to the main power, and the batteries can be recharged at thesame time.

FIG. 10 is a schematic block diagram of a pump unit 100 that correspondsto further details of the pump unit 91 of FIG. 9. It will be appreciatedthat the thick interconnecting lines represent pneumatic connections,while the thin interconnecting lines represent electrical connections.The pump unit 100 includes an independent source of energy, such as arechargeable battery pack 107, which enable the pneumatic deviceoperation without a fixed connection to a main power outlet. Thebatteries can be bypassed and the system is able to operate for longertimes, and the batteries can be recharged at the same time.

A source of compressed air, such as a compressor 104, powered by thebatteries or by the main power, is connected to the sleeve 92 or sleevesby one single pneumatic conduit 94, which enables inflating anddeflating the cells 93. The compressor in this embodiment, can enablethe inverted flow to deflate the cells of the sleeve. It is possible touse a rotary compressor or to enable the inverted deflating flow bymeans of a valve which may be solenoid operated and which is actuated bya control unit 108, or alternatively a pneumatic operated normally openvalve can be used. The valve will be kept closed using the pressure ofthe compressor while the compressor is energized, and will open byitself when the compressor is stopped.

The control unit 108 is adapted to receive the operator's commands andcontrol the operation of the compressor to control the cyclic inflatingand deflating of the sleeve. Solenoid valves are replaced, in thisembodiment, by self-operated relief valves 95, one with each chamber.The compressor is directly connected to the first cell. Each cell isconnected to the next, one through a relief valve to regulate thepressure and maintain a pressure gradient. Each relief valve (except thelast one) is bypassed with a conduit section including a check valve 96to allow deflating of the cell. The last relief valve is open to theatmosphere, thus limiting the maximal pressure in the cells.

The control unit 108 controls the operation of the compressor 104 toinflate the first cell 93. The pressure in the first cell is built-up,and when it gets higher than the first relief valve 95 opening pressure,the second cell starts to be inflated. The third cell is inflated whilethe pressure in the second cell reaches the burst pressure of the secondrelief valve. The inflating process will continue in the same manneruntil the last cell is inflated. When the pressure in the last cellbursts the last relief valve, air will commence to flow out to theatmosphere preventing an uncontrolled pressure build-up inside thesleeve. When the operating interval of the compressor terminates, thecontroller de-energizes the compressor and enables all of the cells tobe deflated simultaneously.

By using self-operated relief valves instead of the controlled solenoidvalves, the system in accordance with the invention will be smaller,lighter, have longer independent operation (as power consumption isreduced), and will be more cost effective. There will be a decrease inthe operational flexibility because the relief valves are self-operated,and the controller can no longer control the inflating sequence of thecells.

The automatic portable ambulant pneumatic pressure system of theinvention is capable of treating more than one part of the body byconnecting more than one sleeve to the pump unit. Sometimes, for medicalreasons, the treatment is not symmetric on the body, i.e., treatmentapplied on the left calf and the right foot, and a different treatmentis required in each sleeve. The sleeves used for the differenttreatments differ from each other by appearance because they aredesigned to operate on a different part of the body. They can alsodiffer with the number of chambers and the connected conduits. The pumpunit has the capability to operate each one of the sleeves with theappropriate medical treatment cycle.

The pump unit can identify the combination of treatments withoutrequesting information from the operator. The operator will select theright sleeves and connect them to the pump unit. That will be sufficientfor the system to identify the required treatment cycles and willprevent the possibility of mismatched input to the system by selecting atreatment, which is not suitable to the fixed sleeves or vice versa.

The control unit, within the pump unit, will read the input informationabout the required treatment by reading the coding of the sleevesconnectors. While starting any new treatment cycle, the control unitwill start the treatment by a quick identification of the type ofsleeves connected and will apply the appropriate operating cycle. Thecoding of the sleeve connectors can be made by state of the artmechanical or electro-mechanical components. It is also possible tostore the required treatment parameters on the sleeve's connectoraccording to the sleeve's projected treatment. On start-up of thesystem, the data will be transferred to the pump unit by way of state ofthe art technology, and the treatment cycle will be compatible to theselected sleeve. The therapist will be able to program the sleeve'sparameters to fit the treatment to the patient.

FIG. 11 is a simplified functional block diagram of an exemplaryembodiment of a connector assembly 1100 for an associated sleeve 1105 inaccordance with the invention. The assembly 1100 includes an electronicmemory and/or control processor unit 1102 that is capable of detectingand transmitting electronic signals. When connected to a pump unit andon power reset of the pump unit, the processor unit, which can be partof the conduits of the sleeve, receives DC power and sends back anidentification signal which initiates the communication procedures. Thetreatment data will be loaded to the pump unit. The second phase of thisoperation is to lock the cuff of the sleeve, with an electromechanicalsafety locking mechanism 1103. This operation is done for safetyreasons, to prevent undesired release of the cuff, during normaloperation.

Another feature is that a pressure sensors array 1104 measures thepressure at the end of each pressure line 1106. The data collected atthis stage is transmitted, via the processor unit 1102, to the processorin the pump unit, in order to evaluate the status of the system. Thesleeve 1105 has several cells that can be independently inflated by thepump unit. The number of cells in the sleeve can vary, according todesired treatments.

Although the present invention has been shown and described with respectto several preferred embodiments thereof, various changes, omissions andadditions to the form and detail thereof, may be made therein, withoutdeparting from the spirit and scope of the invention.

What is claimed is:
 1. An automatic portable ambulant system forapplying pressure to a body limb comprising: a sleeve including firstand second inflatable cells, each of the first and second cellsincluding at least three intra-cell compartments; said intra-cellcompartments being confluent, each compartment being elongated along alongitudinal axis and being substantially rectangular in shape whendeflated and substantially cylindrical in shape when inflated, thelongitudinal axes of the compartments being adapted to substantiallyalign with a primary axis of a body limb, the first and second cellsbeing longitudinally adjacent to each other and being adapted to bearranged coaxially with respect to a primary axis of a body limb, thefirst and second cells being intermittently inflatable to apply pressureto a body limb, wherein each inflatable cell comprises inner and outershells of durable flexible material; said inner and outer shells beingbonded together to form a perimetric cell bond, said perimetric bonddefining outer boundaries of an inflatable cell and boundaries betweenthe inflatable cells, said inner and outer shells being further bondedtogether to form compartmental bonds, said compartmental bonds definingboundaries between intra-cell compartments, wherein the perimetric cellbond includes upper and lower perimetric cell bonds extendingsubstantially in a lateral direction, and left and right perimetric cellbonds extending substantially in the longitudinal direction, and whereinthe compartmental bonds partly extend between the upper and lowerperimetric cell bonds, wherein the compartmental bonds includeperforations to allow for confluent air flow between intra-cellcompartments within a cell, the first cell becoming circumferentiallyconstricted when the first cell is inflated, the second cell becomingcircumferentially constricted when the second cell is inflated, thefirst and second cells being non-confluent such that the first andsecond cells are separately inflatable, said intra-cell compartments ofthe first and second cells being interdigitated; means for laterallycoupling the outermost intra-cell compartments within a cell so as toform a sleeve, the sleeve has a circumference of Nπr when the cell isdeflated, and the sleeve has a circumference of 2Nr when the cell isinflated, where N is the number of intra-cell compartments within thecell, and where r is the cross-sectional radius of each intra-cellcompartment when inflated, so as to provide for circumferentialconstriction; a portable hand-held pump unit for intermittentlyinflating any one or more selected cells of the sleeve via a conduit,said pump unit including a control unit for determining the sequence ofcell inflation and deflation.
 2. The system of claim 1, wherein saidpump unit is battery operated.
 3. The system of claim 2, wherein saidpump unit comprises a rechargeable battery.
 4. The system of claim 1,wherein said pump unit comprises an air compressor.
 5. The system ofclaim 1, wherein said conduit comprises a single tube for deliveringfluid to said sleeve.
 6. The system of claim 1, wherein said conduitcomprises means for indicating to said control unit an appropriateinflation and deflation sequence.
 7. The system of claim 1, wherein saidsleeve comprises at least one self-operated valve.